The Kindle may have a screen that works well in bright light, but the quid pro quo is poor visibility in the dark. No backlight, you see.
Enter M-Edge's e-Luminator Touch, a tiny angle-poise lamp for e-book readers - and paper books too.
M-Edge e-Luminator Touch
The bottom end of the accessory is built like one of those clip- …

What's the colour spectrum of the light?

Please, at least tell us the 'claimed' colour temperature of the LED.

The CRI would be nice as well, but most of these manufacturers don't publish that and I doubt you're set up to measure it!

A lot of consumer LEDs lamps are an extremely high colour temp (often well over 7000K) and use the blue/yellow metamer.

This is mostly because high colour temp appears brighter to the human eye against normal tungsten/warm white CFL, and the blue/yellow metamer is dirt cheap to make as it's just a blue diode with a yellow phosphor dot - but it's got a very poor CRI (~50) and CQS.

These also tend to be very different colours across the beam as well due to the phosphor deposition.

Good white LEDs use UV or deep blue diodes and a mix of phosphors to give a CRI around 80-90, the better ones also give a decent CQS.

These are available in a wide range of colour temperatures, and most people prefer lower colour temps (eg 3000K, normal tungsten) when relaxing.

For reference, 5600K is generally considered normal 'daylight', though a cloudy sky can take the colour temp up as far as 10,000K